Scatter charge



Nov. 22, 1960 s. o. ROCKWELL arm. 2,960,915

SCATTER CHARGE 2 sheets-s3 eat 1 Filed April 12, 1946 INVQENTORS GAY/V050. ROCKWELL GEORGE M. 60 EL 19 w 5 E) BY ATTORNEY Nov. 22, 1960 G. Q.ROCKWELL ETAL 2,960,915

I SCATTER CHARGE 2 Sheets-Sheet 2 Filed April 12', 1946 SCATTER CHARGEFiled Apr. 12, 1946, Ser. No. 661,593

9 Claims. (1. 89-1) The present invention relates to ordnance devicesand more particularly to a novel device for producing a pattern ofexplosive charges. The new device may be used to particular advantage asa means by which a number of contact-type, fast-sinking, antisubrnarineexplosive charges, projected from a surface ship by a single dischargeof a projector, are caused to disperse while in flight to form a patternwhich gives a greater probability of securing a hit. It is to beunderstood, however, that the invention is not limited to this use.

It has been proposed heretofore to scatter explosive charges for useagainst submarines by providing a bundle of explosive projectilessurrounding a dispersal mechanism and held in place by a steel strap,dispersal of the projectiles and breaking of the strap beingaccomplished by electrically operated explosive charges fired after thebundle has been projected from a K-gun or other projector. Devices ofthis type, as heretofore proposed, have not been satisfactory because ofoperational difiiculties encountered in dispersal of the projectilesfrom the bundle.

One object of the present invention, therefore, resides in the provisionof a device for producing a pattern of explosive charges and includingnovel charge-dispersing means which overcomes the difhculties previouslyencountered with prior dispersal means.

Another object of the invention is to provide a device of the characterdescribed having the charges or projectiles normally held together in abundle by a binding strap, and which includes dispersal means in theform of a mechanical shear adapted to be driven by an explosive force tobreak the binding strap.

Still another object is to provide a device of the character describedhaving an inertia-operated safety device for insuring against prematureoperation of the dispersing means for the charges.

A further object is to provide a device of the character describedhaving an improved container for the dispersing charge.

' These and other objects of the invention may be better understood byreference to the accompanying drawings, in which Fig. 1 is a perspectiveview of a bundle of antisubmarinecharges embodying the presentinvention, showing the bundle loaded in a K-gun;

Fig. 2 is a perspective view of the working head of the dispersal meansfor the charges shown in Fig. 1;

Figs. 3 and 4 are horizontal and vertical sectional views, respectively,of the working head;

Fig. 5 is an enlarged, fragmentary, transverse sectional view of theworking head, showing the operating switch and the container for thescattering charge and detonator;

Fig. 6 is a perspective view, partly in sections of the operating switchfor the working head, and

Fig. 7 is a diagrammatic view of the firing circuit.

Referring now to Fig. 1, contact charges in the form of antisubmarineprojectiles it) are bound up in a bundle 11 by meansof a steel strap 12.As shown, the bundle 11 comprises six projectiles 10, although it willbe under stood that any other desired number of projectiles may be used.The projectiles 10 surround a working head included in the bundle 11 anddescribed in detail below. The bundle of projectiles is secured to astandard depth charge arbor 13 by a cable 14 having a shear pin device(not shown) which is broken upon firing or projecting the bundle from aK-gun 15. A block 16 on the arbor 13 insures proper location of thebundle of projectiles with respect to the arbor. The K-gun 15 may be ofstandard design and has a chamber 15a adapted to receive an explosivepropelling charge which acts on part of the arbor 13 extending into themuzzle of the gun, to project the bundle 11 from the gun.

Referring now to Figs. 2, 3 and 4, the working head 18 comprises a maincylindrical body 19 containing six equally spaced pistons 20 operatingin radial cylinders 21. On the outer end of each piston 20 is a saddleor pressure plate 22 curved to conform to the cylindrical surface of thecasing of the adjacent projectile 10. Also attached to the body 19 ofthe working head is a strap shear consisting of frame members 23connected to the body 19 and extending radially therefrom, a shear bar24 connected between the outer ends of the frame members, and a shearblade 25 attached to a shear piston 26 which operates in a radialcylinder 27 in body 19. The shear blade 25 is disposed between themembers 23 and is movable radially of the body 19 in guides 28 on theframe members. The strap 12 passes between the shear bar 24 and theshear blade 25. A dispersing charge 30 and its associated time-delaydetonator 31 are inserted in a central cavity 32 in the body 19 and areretained by a cover plate 33 bolted on the supper face of the body. Thecavity 32 communicates directly with the cylinders 21 and 27.

In the operation of the device, the time-delay detonator 31 explodes thescattering charge 30 at a predetermined time subsequent to firing of thebundle 11 from the K-gun. Explosion of the scattering charge 39 producesa high gas pressure in the chamber 32 which forces the pistons 20 and 26outward. Outward motion of piston 26 forces the shear blade 25 past theshear bar 24 cutting the strap 12. When the strap 12 is cut, the charges10 are released and forced outward by the pressure in cavity 32 actingagainst the pistons 23.

The dispersing charge 30 is held in a container constructed in twoparts, an insulating cap 34 and a cup 35, the time-delay detonator 31being held in a threaded metal holder 36 screwed into the cap 34. Theentire assembly is inserted in the central cavity 32 of the main body 19with the edge of the cap 34 hearing on the bottom of a counterboredsection of the cavity. The edge of the cap 34 is bevelled at 34a topermit it to expand to form a gas-tight seal with the wall of the cavity32 when the dispersal charge explodes. The cover plate 33 is recessed tofit over the upper end of the cap 34.

The detonator 31 is electrically fired. More particularly, electricalconnections to the detonator are made through a central contact pin 4%and the body of the holder 36, respectively. The contact pin 40' extendsthrough an insulating bushing 41 in cover plate 33 and is urged againstthe central insulated contact 36a of the holder 36 by the action of aspring 42 hearing against a shoulder on the pin. A grounding spring 44is secured directly to the cover plate 33 and bears against the metalpart of the holder 36 surrounding the insulated contact 3601 and thedetonator 31. A toggle switch 45 is carried on a bracket 46 attached tothe outer surface of the cover plate. This switch is operated at thetime of firing of the K-gun by the inertia of a weight 47 attached toits operating handle 47a (Figs. 4- and 5). A safety pin 48 is threadedat its lower extremity into a hole in the cover plate 33 and when inplace prevents motion of the weight 47 and removes the danger ofpremature ignition of the dispersing charge. A neck 49 on the safety pinjust above the threaded tip makes it possible to twist the pin ofi? inthe event that the threaded portion is stuck by corrosion. A cover 50protects the switch assembly.

Referring to Fig. 7, the ignition circuit for the scattering charge 30operates in parallel with that for the K-gun propelling charge. When thefiring switch 52 on the K- gun 15 is closed, current flows from abattery 53, or other current source, through a detonator 54 in the K-gunto explode the propelling charge in chamber 15a. Upon acceleration ofthe arbor and the projectile bundle 11, the inertia of the weight 47causes it to move, closing the safety switch 45. Sufiicient slack isleft in wire 55 connecting the switch 45 with the K-gun firing circuitto maintain the electrical connection between the projectile bundle 11and the gun, after the bundle starts to move from the gun, and to allowtime for current to flow through the switch 45 and initiate operation ofthe timedelay detonator 31. It will be understood that the timedelaydetonator 31 is connected to one side of battery 53 on the K-gun throughthe insulated conductors 36a and 40, the switch 45 and the slack wire55, and is connected to the other side of the battery through metalholder 36, grounded spring 44, body 19, bundle 11 and the part of arbor13 projecting into the K-gun, the latter connection being designated inFig. 7 by the reference numeral 57. On firing of the K-gun, the part ofarbor 13 projecting into the gun remains in contact with the gun for asufficient time interval to cause complete energizing of the time-delaydetonator 31 through the circuit described above. The detonator 31,after being thus energized, is operable to explode the dispersing charge30 after a predetermined time interval which is dependent upon the knowntrajectory of the bundle 11.

In operation, the safety pin 48 is removed to release the weight 47after the K-gun is loaded. The operating switch 52 of the K-gun is thenclosed to fire the propelling charge 54 in the gun, whereupon the cable14 is sheared and the bundle 11 with arbor 13 is discharged from thegun. Upon firing of the gun, the force of setback on the weight 47, dueto its inertia causes the weight to close the switch 45 so that thecircuit previously described through detonator 31 is closed. The circuitremains closed until the wire 55 is broken or the part of the arbor 13normally extending into the K-gun barrel leaves the gun, this timeinterval being sufiicient to initiate operation of the time-delaydetonator 31. After the time interval provided by the detonator 31 andbefore the bundle 11 strikes the water, the charge 30 is exploded, andthe resulting force on pistons 20 and 26 severs the strap 12, aspreviously described, and expels the projectiles from the head 19. Thus,the projectiles 10 are dispersed outwardly from the head 19 and enterthe water in a pattern which is calculated to effect a hit on asubmarine in the pattern area. Upon contacting the submarine, any one ofthe projectiles 10 is detonated by the usual contact fuze (not shown).

It will be apparent that the new device is of simple construction andincludes highly effective safty means for preventing premature operationof the dispersing detonator 31. The dispersing device for the charges orprojectiles is positive and reliable in operation and is of a compactform so that the projectiles may be clustered closely around the devicein a compact bundle.

We claim:

1. In combination, a plurality of objects to be dispersed, a binder forholding said objects together in a bundle preparatory to the projectionof said bundle into space, and a working head in said bundle having anexplosiveoperated cutter for shearing the binder and havingexplosive-operated pistons for dispersing said objects outwardly fromthe head in a pattern during projection of the bundle.

2. Means for dispersing a plurality of objects, said means comprising acurrent source grounded at one side to a gun from which the objects areintended to be dispersed, an arbor having a part projectable into thegun bore from the muzzle end of the gun, a plurality of projectiles onthe arbor, a binder for holding the projectiles and arbor together in abundle, a working head in said bundle having an explosive charge forshearing the binder and dispersing the projectiles from the head in apattern, an electrically operable detonator in the head for explodingsaid charge, means for grounding one side of the detonator through thebundle to the gun, whereby the detonator is connected to said side ofthe current source, and a conductor for connecting the other side of thedetonator to the other side of said current source and having suflicientslack to enable energization of the detonator from the current sourceafter firing the gun.

3. Means for dispersing a plurality of objects, said means comprising anarbor having a part projectable into the bore of a gun from the muzzleend of which the arbor is to be fired, a plurality of projectiles on thearbor, a binder for holding the projectiles and arbor together in abundle, a working head in said bundle having an explosive charge forshearing the binder and dispersing the projectiles from the head in apattern, an electrically operable time-delay detonator in the head forexploding said charge and grounded at one side to the gun through saidhead and bundle, a current source grounded at one side to the gun, aconductor connecting the other side of the current source with the otherside of said detonator and having a substantial amount of slack, anelectrically operable detonator for firing the gun and connected acrossthe current source in parallel with said first detonator, and a switchbetween the current source and said detonators for energizing thedetonators substantially simultaneously.

4. A device for dispersing objects in a pattern, which comprises aworking head having a central cavity and cylinders radiating from thecavity, pistons in the cylinders, means on the outer ends of the pistonsfor supporting said objects in a cluster about the working head, anexplosive charge in the cavity for forcing the pistons outwardly in thecylinders to disperse said objects in a pattern, an electricallyoperable detonator in the head for firing said charge, a normally openarming switch on the head through which the detonator is adapted to beenergized, and means operable by a force of setback to close the switchfor energizing the detonator.

5. A device for dispersing objects in a pattern, which comprises aworking head having a central cavity and cylinders radiating from thecavity, pistons in the cylinders, means on the outer ends of the pistonsfor supporting said objects in a cluster about the working head, anexplosive charge in the cavity for forcing the pistons outwardly in thecylinders to disperse said objects in a pattern, an electricallyoperable detonator in the head for firing said charge, a normally openarming switch on the head through which the detonator is adapted to beenergized, means operable by a force of setback to close the switch forenergizing the detonator, and releasable safety means for locking saidsetback means against operation.

6. A device for dispersing objects in a pattern, which comprises aworking head having a central cavity and cylinders radiating from thecavity, pistons in the cylinders, means on the outer ends of the pistonsfor supporting said objects in a cluster about the working head, a cupin said cavity, an explosive charge in the cup for forcing the pistonsoutwardly in the cylinders to disperse said objects in a pattern, a capclosing said cup and having a central opening, an electrically operabledetonator in the cup for exploding said charge, a metal holder for thedetonator mounted in said opening and in current conducting relation toone side of the detonator, the holder hav- "ing an insulated conductorconnected to the other side of the detonator, a cover plate on the headfor retaining the parts in the cavity, a contact spring grounded on thecover plate and engaging the holder, a contact pin in the cover plate,means for insulating said pin from the plate, a spring for urging thecontact pin against said conductor on the holder, and a setback switchon the cover plate connected to said contact pin and through which thedetonator is adapted to be energized.

7. A device for dispersing objects in a pattern, which comrpises aworking head having a central cavity and cylinders radiating from thecavity, pistons in the cylinders, means on the outer ends of the pistonsfor supporting said objects in a cluster about the Working head, acutter operable by one of the pistons for releasing said objects fromthe head, and an explosive charge in the cavity for forcing the pistonsoutwardly in the cylinders to operate the cutter and disperse saidobjects in a pattern.

8. In combination, a plurality of projectiles, a working head having acentral cavity and cylinders radiating from the cavity, pistons in thecylinders, saddles on the outer ends of certain of the pistons forsupporting the projectiles, a binder for securing the projectiles in abundle on the saddles; a cutter on the head for shearing the binder andconnected to one of the pistons, and an explosive charge in the cavityfor forcing the pistons outwardly to operate the cutter, therebyreleasing the pro jectiles, and to disperse the projectiles in apattern.

9. In combination, a plurality of projectiles, a working head having acentral cavity and cylinders radiating from the cavity, pistons in thecylinders, saddles on the outer ends of certain of the pistons forsupporting the projectiles, a binder for securing the projectiles in abundle on the saddles, a frame on the head extending outwardly therefrombetween adjacent projectiles and having a shear bar engaging the outeredge of the binder, a cutter guided in the frame and movable by one ofthe pistons to shear the binder against said bar and release theprojectiles, and an explosive charge in the cavity for forcing thepistons outwardly to operate the cutter and disperse the projectiles ina pattern.

References Cited in the file of this patent UNITED STATES PATENTS1,146,950 Pivonka July 20, 1915 1,295,213 Saladiner Feb. 25, 19192,335,927 Firth Dec. 7, 1943 2,346,494 Leland Apr. 11, 1944 2,399,248Patrick et al Apr. 30, 1946 2,411,432 Imber Nov. 19, 1946

